The number of people who have arthritis is increasing. It is currently estimated that between 35-40 million people in the United States alone, or one out of every seven individuals, has arthritic symptoms which require medical treatment. There will be one person every thirty three seconds who will develop symptomatic arthritis and need medical treatment.
Despite the introduction of newer, non-steroidal drugs designed to treat the arthritic patient, aspirin remains the drug of choice. Aspirin has both anti-inflammatory and pain relieving benefits. In the reference pharmacology textbook, Goodman and Gilman, The Pharmacological Basis of Therapeutics, 6th Edition, Section V, Chapter 28, the entire section on analgesic, anti-inflammatory drugs is characterized as follows: "The anti-inflammatory, analgesic and antipyretic drugs are a heterogenous group of compounds often chemically unrelated which nevertheless share certain therapuetic actions and side effects. The prototype for these compounds is aspirin."
One problem with aspirin, as usually formulated for typical, commercial formulations is that it has to be administered four to six times a day to produce satisfactory pain relief and suppression of inflammation. When drugs or medications have to be administered more than twice daily, patient compliance is approximately forty five (45%) percent. When the therapeutic agent is given once or twice daily, compliance by the patient increases to about seventy five (75%) percent. Further, standard aspirin formulations can produce a high incidence, seventy (70) percent, of gastrointestinal side effects including nausea, heartburn, vomiting, gastric erosion, gastro-duodenal ulcers as well as bleeding from the gastrointestinal tract. Approximately twenty-five (25) percent of patients taking regular aspirin tablets complain of ringing in the ears and other central nervous system side effects.
Because of the side effects of this valuable, therapeutic agent, there has been a long standing need for an aspirin product which can be taken once or twice daily and which provides a slow, steady release of aspirin to decrease side effects without loss of efficacy. The present invention provides one such product.